The U.S. government must pay a pair of local water districts $2.4 million for water promised but often not delivered from New Melones Lake, a judge ruled this week.

That's far less than the $37 million to $42 million collectively sought by the Stockton East and Central San Joaquin water districts.

"It's a shame. We think we should have gotten more," Stockton East General Manager Kevin Kauffman said Friday.

"Were we treated fairly? I don't think so. What are we going to do about it? I don't know."

The districts signed a contract for New Melones water in 1983 and built a $65 million tunnel to take it - financed by Stockton ratepayers and home buyers.

But the U.S. Bureau of Reclamation later refused to turn on the spigot.

The districts sued in 2004 and eventually prevailed in federal court. On Thursday, U.S. Court of Federal Claims Judge Christine Odell Cook Miller awarded damages.

Most of the $2.5 million goes to Stockton East, which provides both city drinking water and irrigation flows for farmers.

While limited, the money does exceed the cost of the litigation and could be used on projects to help recharge the county's sinking groundwater supply, Kauffman said.

"It can't hurt," he said.

But, he added, it doesn't come close to making up for losing the water.

"If they hadn't breached (the contract), we would have been where we are today almost 20 years ago - planning to do groundwater recharge, to build infrastructure to give farmers a better chance to use the water," Kauffman said.

The judge, however, dismissed Stockton East's claims that it could have taken the water if it was available.

The judge found that a pipeline crucial to delivering the water to Stockton East's treatment plant would not have been built in time to use all that water, in part because the city had "serious concerns" about the financing plan.

Nor did Stockton East prove it had the capacity at its plant to treat additional New Melones water, the judge ruled.

She criticized as "speculative" Stockton East's calculations of the damages to which it argued it was entitled.

She did award the district limited damages based on its need to buy a replacement water supply from districts on the Stanislaus River once it became clear New Melones water would not be consistently delivered.

Kauffman said his district would consult with its attorneys and consider an appeal. A spokesman for the Bureau of Reclamation said officials were reviewing the decision and could not yet comment.

Federal officials have previously said it became difficult to provide New Melones water to Stockton because of increasingly strict environmental laws requiring water to be released down the river.

Damages aside, the bureau has provided full New Melones allocations in recent years, which Stockton East officials have attributed in part to pressure brought through the litigation.

Just on Monday, the bureau announced another full allocation for the districts, despite increasingly dry conditions.